Skip hoist



April 1944- 6. FOX ET AL 2,345,662

SKIP HOIST Filed Feb. 25, 1942 a Sheets-Sheet 1 INVENTOR. G ordon Fox BY Olaf C.Callow UM A474, @w mawwzsw G. FOX ET AL April 4, 1944.

SKIP HOIST Filed Feb. 23, 1942 5 Sheets-Sheet 2 Fig. 4-

' Fig.5

INVENTOR. Gordon Fox BY glaf C. Collow harles G. 1' elow Z JM-M-4 /r- ,4z" ir ya.

April 4, 1944. ox ETAL 2,345,662

SKIP HOIST Filed Feb. 23, 1942 5 Sheets-Sheet 3 INVENTOR. Gordon FOX BY Ola C.Ca llow Patented Apr. 4, 1944 SKIP KOIST Gordon Fox, Olaf C. Callow, and Charles G. Bigolow, Chi

cago, 111., asslgnors to Freya Entineer ing Company, Chicago, 111., a corporation of Maine Application February 23, 1942, serial No. 432,060,

Claims. (01. 254-186) The present invention relates to improvements in skip hoists.

More particularly the present invention relates to skip hoists applicable to raising and lowering the skip tubs associated with a blast furnace. It is common practice to provide a pair of skip tubs for each blast furnace, said tubs being arranged so that while one is ascending the other is descending. It is common practice to mount th cables for two skip tubs upon a single drum, the cable attached to one tub unwinding as the cable attached to the other tub winds up upon the drum. It is also common practice to provide a pair of drums, one associated with each of the cables.

An object of the present invention is to provide a skip hoist mechanism which is rigid, relatively simple to construct, and amply sturdy to withstand the stresses encountered in service.

A further object is to provide a skip hoist hav-- ing the parts thereof symmetrically disposed upon a firm though relatively, light-weight foundation, which skip hoist is compact and efficient in service.

A further object is to provide a skip hoist having the parts thereof so disposed that servicing of said skip hoist may be readily accomplished and whereby economy of manufacture, shipping convenience, accuracy of initial alignment and maintenance of alignment may be had.

A further object is to provide a skip hoist in which relatively high speed motors may be used with brakes of moderate size.

A further object is to provide an improved skip hoist having a double drive, the parts being so disposed that either drive may be put out of service for repairs or the like while the other drive is being used to operate the hoist.

A further object is to provide an improved skip hoist which reduces the stress on the drum shaft bearings below that common in practice.

A further object is to provide a double drum skip hoist in which space is conserved and the distance between drum bearings is reduced.

A further object is to provide a skip hoist in which speed reducing gear mechanisms may be applied as units rather than being assembled at the blast furnace to fit any specific job.

A further object is to provide an improved skip hoist in which the reliability. of the brakes is improved.

A further object is to provide a skip hoist having a pair of brakes in a combination involving two complete drives for the winding drum or drums. whereby it is possible to uncouple and remove one of the operating motors without in-' terrupting operationsby the other motor. A further object is to provide a skip hoist readily adaptable for different types of job while refor said low-speed pinions may .all be substan-' tially standard.

Further objects will appear asthe description proceeds. 1g 1' Referring to the drawingst Figure 1 is a top plan view of a skip ing asingle' drum adapted to have two cables mounted thereon, each associated with askip tub of a blast furnace, which skip hoist embodies the principles or the present invention;

Figure 2 is a view in side elevation of the construction illustrated in Figure 1;

Figure 3 is a view in end elevation of the struction illustrated in Figure 1;

Figure 4 is a view of a double-drum skip hoist illustrating the principles of the present invention, the motor drives and reducer units being con- ' omitted inasmuch as these mechanisms may take the'form illustrated in Figure 1;

Figure 5 is a view in side elevation of the structure shown in Figure 4;

Figure 6 is a more or less diagrammatic view of .the bed plate illustrated in Figure 1, the instrumentalities carried thereby having been removedalong the plane indicated by the arrows Hl l of Figure 7.

The numeral 20 indicates a bed Plate which includes two elongated members 2l'-2l, illus-.

trated at H-beams. Said elongated members 2l-2l are connected together by a plurality of cross members welded or otherwise secured to said members 2l2i and located at regions to provide flrm support for the instrumentalities (to be referred to later) carried by the bed plate 20. Certain of the cross members referred to are indicated in Figure 6 by the numerals 22, 23, 24, 25.

v26, 21, 28 and 29. 'Said cross members are welded or otherwise secured to the flanges and the webs hoist havof the H-beams 2l-2l. Said cross members 22 and 23 support a plate 30. Said cross member 24 assists in supporting thetwo plates 3l-3l, each of which is substantially symmetrically disposed with respect to its respective H-beam 2|.

The cross members 25 and 26 support the plate 32, and the cross members 21 and 28 support the plate 33. The cross member 29 assists in supporting the platforms 34-34. Other bracing member will be provided to insure rigidity in the base plate 20. It is not considered necessary to illustrate or describe in detail said other bracing members. The numerals 35-35 indicate pads for mounting certain instrumentalities of the hoist.

Referring now to Figures 1, 2 and 3, the numeral 40 indicates a drum, which, as indicated hereinabove, is adapted to have two cables disposed thereon, each of said cables being connected to a corresponding skip tub, one of said cables unwinding from the drum as the other winds up, and winding back upon said drum as ing H-beam through one of the plates 3| and through a spacer 55a.

For supporting the overhanging portions of the two speed reducing gear units 50-50, each of the two H-beams 2 l-2l is provided with an outwardly said other cable unwinds during reverse-rotation of the drum.

Secured to said drum 40 is a spider (not illustrated) which carries a low-speed gear 4|, which may take the form of a herringbone gear. Said drum, spider and low-speed gear are coaxially disposed upon the shaft 42, which shaft 42 is carried by the two bearing pedestals 43 and 44, which may be equipped with bearings of any preferred type.

The present invention contemplates two complete drives for the drum 40. Said two complete drives include the electric motors 45 and 46 mounted upon the platforms 34-34, each of said motors being connected to a corresponding flexible coupling member 41. The driven side of each flexible coupling member 41 is connected to a corresponding extension shaft 48, each of the shafts 48 being provided with a brake engaging member adapted to be controlled by a corresponding brake 43.

Each of the shafts 48 (which shafts may be referred to as high-speed shafts) is connected directly to the high-speed shaft of a corresponding speed reducing gear unit 50. Extending outwardly from each speed reducing gear unit 50 is a corresponding intermediate-speed shaft 5| carrying a corresponding pinion 52 meshing with the low-speed gear 4|.

Each of the shafts 5l-5l is provided at its extremity with a corresponding outboard bearing 53, which outboard bearings 53-53 are carried in corresponding pedestals 54-54. Said pedestals 54-54 rest upon the plates 3l-3l and are removably secured to the bed plate 20 by means of construction which will be described presently.

The two electric motors 45 and 46 are carried by the platforms 34-34. The two speed reducing gear units 50-50 are removably supported by the plate 33, the pedestal 44 is supported by the plate 32, and the pedestal 43 is supported by the plate 30.

Each of the pedestals 54-54 for supporting the outboard bearings 53-53 of the intermediatespeed shafts 5l-5l is adapted to be secured to the corresponding side of the bed plate 20. Each of said pedestals has a base portion resting upon and adapted to be secured to its corresponding plate 3|. Each of the H-beams 2 l-2l has welded or otherwise secured thereto a corresponding outwardly presented vertically disposed plate 55 adapted to receive and to have bolted thereto the lower portion of the corresponding pedestal 54. said plate 55 being secured to its correspondpresented plate 56 adapted to have bolted thereto a corresponding shelf or bracket 51.

By reason of the fact that the pedestals 54-54, the gear units 50-50 and the brackets 51-51 are removably secured to the bed plate 20, the advantage is'had that these members may be removed from the bed plate durin shipment, thereby conserving dimensions to conform with permissible railroad clearance limits.

Referring to the double drum hoist illustrated in Figures 4 and 5, the intermediate-speed shafts 5l-5l leading from the speed reducer gear units are coupled to the shafts 58-58. Said shafts 58-58 are provided with the pinions 59-59 meshing with the low-speed gear 60, which may take the form of a herringbone gear. Each of said shafts 58-58 is mounted within bearing pedestals 6I-6l. The pedestals associated with each shaft 58 are disposed at the two extremities of their corresponding pinion 59.

The low-speed gear 60 is disposed between the two winding drums 62 and 63, being secured to the shaft 64 and to said winding drums. Said shaft 64 is rotatably carried by the bearing pedestal 65 adjacent to its right-hand end as the parts are viewed in Figures 4 and 5, and by the bearing pedestal 66 adjacent to its left-hand end.

According to the present invention a decided advantage is had because two complete drives are provided carrying through from the driving motors to the winding drum or drums. An advantage of the double drive results from the fact that it is feasible to eliminate the use of brakes applied directly upon the winding drum. According to the present invention it is possible to operate the winding motors at a higher speed than has been practicable with devices in the prior art. In view of this fact, a high gear ratio is used between the driving motors and the drum shaft. Because of this high gear ratio, brakes of moderate size, applied to the high-speed motor shafts, have adequate capacity to hold the load and to decelerate the load in emergency.

The double drive according to the present invention offers the further advantage that a single motor can be used to operate the hoist while the other motor and its associated shaft and speed reducing unit are out of service for repairs or for any other reason.

A further advantage of the double drive according to the present invention results from the fact that in normal operation the uplifting force at one drum pinion is equalized by the'downwardly acting force at the other drum pinion. The only vertical forces on the drums are due to the upward pull of the cables and the downward pull of gravity. These are substantially equal in both directions of rotation. According to the prior art, wherein a single low-speed pinion was employed, the reaction from this pinion was upward for one direction of rotation and downward for the other direction ,of rotation. This imposed heavier service on the drum shaft bearings.

It is to be noted also that any tendency to spread between the pinions 52-52 is firmly reassumes 54-54 which carry the bearings for the shafts Il-il adjacent to said pinions "-42.

The .double drum hoist shown in Figures 4 and 5 is arranged with the low-speed gear ll located in the space between the two winding drums. There are advantages in spacing the two winding drums apart to conform approximately with the center line distances between the tracks upon which the two skips operate. The utilization of this space for the low-speed gear 80 results in a reduction in the total axial space occupied by the hoist, as contrasted with the prior art, in which the driving gear was arranged at one end of the double drum barrel. A further advantage accruing from the double drive as embodied in the present invention is that a symmetrical drive is obtained with torque transmission from the lowspeed gear to one drum on either side thereof. .In' previous hoists involving two winding drums it was frequently the practice to locate the drum brake in the region between the drums. Inasmuch as the present invention does not require a drum brake, this region is usefully employed for the location of the low-speed gear 60. The present invention, inasmuch as it eliminates winding drum brakes and utilizes the space between the drums for the low-speed gear 60, has the advantage of minimizing the length of the drum barrel and the distance between the drum bearings.

According to prior practice it has been common for the hoist manufacturer to fabricate the high'- speed gears as part of the hoist mechanism. These gears, their supports and their enclosures have been in the nature of a tailor-made job, laid out and machined on the basis of individual production. Several advantages accrue from the present invention from the use of speed reducing gear units which are gear factory built and have the benefits of mass production withreference both to accuracy and economy of manufacture. Furthermore, these speed reducing gear units can be and are run in at the gear factory, so that the teeth are in good condition before the hoist is put into service. Furthermore, since the speed reducing gear units are unitary constructions, they can be dismantled as such, and the gears can be protected during shipment. This practice is to be contrast-ed with the previous practice, in which the elements of the high-speed gearing were dismantled, involving the danger that reassembly might not correspond exactly with the original assembly at the hoist factory.

According to the present invention, two brakes 49-49 are employed. These brakes may be of a commercially available type which is economical. The brakes may be identical, contributing to operation in unison. With the brakes located as illustrated in Figures 1 and 2, it is possible to uncouple and to remove one motor armature, operating the hoist with the other motor, and retaining both brakes in service, an advantage which is important because of the safety factor afforded thereby. The arrangement referred to has the further advantage that the two brakes operate through a minimum number of intermediate links. Either brake functions through two gear reductions and two shafts. But the winding motors l5 and 46 and their flexible couplings 4|4l are not included in the braking circuit.

The structure according to the present invention has certain commercial advantages inview of the fact that the gear units can be made substantially standard both for the single drum and double drum hoists, and for hoists operating at 75 dri 3 differing speeds. Such changes in gear ratio as may be desired from one job to another can be obtained by employin commercial speed reducing gear. units of fixed physical dimensions but pedestals, low-speed pinions, andpedestal bearings, all of which are substantially standard.

It will be ted that the intermediate-speed shafts il-Bl are located substantially symmetrically above their corresponding H-beam members 2l -2l, the outboard bearing (mounted in the pedestal lit-Figs. 1 and 2) and the bearings mounted in the pedestals 8 l--6| (Figs. 4 and 5) being mounted upon said H-beam members il-fl. Each speed change gear reducer unit 50 is carried generallyabove its corresponding [-lbeam member 2|. In this manner a firm foun dation is provided for the intermediate speed shafts Sl-Bl (Figs. 1, 2, 4 and 5) and the intermediate speed shafts 58-58 (Figs. 4 and 5). 1

The symmetrical arrangement of the hoist results in compactness and minimizes space requirements. The rectangular shape contributes to this conservation ofv space. This is in contrast to conventional hoists, which commonly have floor plans of generally Z-configuration. The onepiece bed plate 20, which is made up by welding together structural steel members, has substantial advantages in rigidity as contrasted with Z-shaped bed plates. A further advantage of the symmetrical arrangement according to the present invention resides in the fact that the drum bearings, change speed gear reducer units, and motors are all symmetrically disposed, whereby they can be satisfactorily served by a single overhead trolley mounted on an I-beam located above the center line of the hoist.

Decided practical advantages accrue from'the fact that the rectangular bed plate 20 is made in one piece. This bed plate, which includes the two parallel side members, the cross members and the supporting plates carried by said parallel side members and said cross members, may be put into a planar and all the surfaces of the supporting plates can be planed simultaneously. Said supporting plates carry the pedestal bearings, the gear reducing units, the brakes and the motors. and it is accordingly a simple matter to provide accurately machined surfaces for receiving these instrumentalities. This leadsto a more accurate alignment in assembly than has been possible with prior structures.

Though certain preferred embodiments of the present invention have been described in detail, many modifications will occur to those skilled in the art. It is intended to cover all such modifications that fall within the scope of the appended claims.

What is claimed is:

1. In a skip hoist; in combination, a rectangular bed plate including a pair of parallel members each having a vertically disposed supporting portion, cross members connecting said members, bearing pedestals carried by said cross members, drum means and a gear carried by said bearing pedestals, said drum means and said gear being secured together, a pair of pinions meshing with said gear, intermediate speed shafts for said pinions, a pair of electric motors, and independent drive means connecting each of said motors with a caresponding one of said pinions, each of said means including speed reducing means connected to said intermediate speed shaft and to its corresponding motor, said intermediate speed shafts and said pinions being supported by and being disposed directly above and in substantially symmetrical relationship with the vertically disposed supporting portions of said side members.

2. In a skip hoist, in combination, a rectangular one-piece bed plate including a pair of parallel members each having a vertically disposed supporting portion, cross members connecting said members, bearing pedestals carried by said cross members, drum means and a gear carried by said bearing pedestals, said drum means and said gear being secured together; a pair of pinions meshing with said gear, intermediate speed shafts for said pinions, a pair of electric motors, and independent drive means connecting each of said motors with a corresponding one of said pinions, each of said drive means including speed reducing means connected to said intermediate speed shaft and to its corresponding motor, said intermediate speed shafts and said pinions being supported by and being disposed directly above and in substantially symmetrical relationship with the vertically disposed supporting portions of said side members, each of said drive means including a flexible coupling between its corresponding motor and its corresponding speed reducing means.

3. In a skip hoist, in combination, a rectangular bed plate including a pair of parallel members each having a vertically disposed supporting portion, cross members connecting said members, bearing pedestals carried by said cross members, drum means and a gear carried by said bearing pedestals, said drum means and said gear being secured together, a pair of pinions meshing with said gear, intermediate speed shafts for said pinions, a pair of electric motors, and independent drive means connecting each of said motors with a corresponding one of said pinions, each of said drive means including speed reducing means connected to said intermediate speed shaft and to its corresponding motor, said intermediate speed shafts and said pinions being supported by and being disposed directly above and in substantially symmetrical relationship with the vertically disposed supporting portions of said side members, one of said cross members being located to tie together said side members at the parts thereof adjacent to said pinions.

4. In a skip hoist, in combination, a rectangular bed plate including a pair of parallel members each having a vertically disposed supporting portion, cross members connecting said members, bearing pedestals carried by said cross members, drum means and a gear carried by said bearing pedestals, said drum means and said gear being secured together, a pair of pinions meshing with said gear, intermediate speed shafts for said pinions, a pair of electric motors, and independent drive means connecting each of said motors with a corresponding one of said pinions, each of said drive means including speed reducing means connected to said intermediate speed shaft and to its corresponding motor, said intermediate speed shafts and said pinions being supported by and being disposed directly above and in substantially symmetrical relationship with the vertically disposed supporting portions of said side members, each of said drive means including a coupling between its corresponding motor and its. corresponding speed reducing means, each of said drive means being provided with a brake located on that side of said coupling adjacent to its corresponding speed reducing means.

5. In a skip hoist, in combination, a substantially rectangular bed plate including a pair of side members each having a vertically disposed supporting portion, drum means located on said bed plate symmetrically with respect to said side members, a gear fast to said drum means, pinions meshing with said gear, said pinions being symmetrically disposed with respect to said gear and having their axes disposed in substantially coplanar relationship with the vertlcally disposed supporting portions of said side members, intermediate speed shafts coaxially disposed with said pinions, speed reducing means each disposed symmetrically with respect to a corresponding vertically disposed supporting portion of said side members, one side of each of said speed reducing means being connected to its corresponding intermediate speed shaft, and an electric motor connected to the other side of each of said speed reducing means.

6. In a skip hoist, in combination, a substantially rectangular bed plate including a pair of parallel side members extending substantially the length of said bed plate and each having a vertically disposed supporting portion, drum means located on said bed plate symmetrically with respectto said side members and on the center line of said bed plate, a gear fast to said drum means at one end thereof, pinions meshing with said gear, said pinions being symmetrically disposed with respect to said gear, intermediate speed shafts connected to and coaxially disposed with respect to said pinions and extending in parallel relationship away from said drum means directly above said parallel side members, speed reducing means incorporating said intermediate speed shafts and symmetrically disposed in relation thereto, an electric motor connected to the other side of each of said speed reducing means, and a brake for each of said motors, the two said motors being located adjacent to each other and symmetrically with respect to the center line of the hoist.

7. In a skip hoist, in combination, a substantially rectangular bed plate including a pair of parallel side members each having a vertically disposed supporting portion, drum means located on said bed plate symmetrically with respect to said side members, a gear fast to said -drum means, pinions meshing with said gear, said pinions being symmetrically disposed with respect to said gear and having their axes substantially directly above the vertically disposed supporting portions of said side members, intermediate speed shafts coaxially disposed with said pinions, speed reducing means, one side of each of said speed reducing means being connected to its corresponding intermediate speed shaft, and an electric motor connected to the other side of each of said speed reducing means, said motor being disposed adjacent to the center line of said drum means.

8. In a skip hoist, in combination, a one-piece substantially rectangular bed plate including a pair of side members extending substantially the length of said bed plate, drum means located on said bed plate symmetrically with respect to said slide members, a gear fast to said drum means, pinions meshing with said gear, intermediate speed shafts coaxially disposed with said pinions directly above said side members, speed reducing units, one side of each of said units being connected to its corresponding intermediate speed shaft, an electric motor connected to the other side of each of said speed reducing units, and a brake for each of said motors.

9. In a skip hoist, in combination, a one-piece bed plate, a pair of pedestal bearings carried by said bed plate, a shaft carried by said pedestal bearings located substantially symmetrically with the center line of said bed plate, drum means fast with said shaft, a gear fast with said drum means, a pair of pinions meshing with said gear diametrically with respect to said gear, a pair of intermediate shafts carrying said pinions, a pair of independent gear reducing means each connected on one side thereof to a corresponding one of said intermediate shafts, and ,a pair of motors having their shafts located parallel to and adjacent to the center line of said hoist, said two motors being connected to said two gear reducing means.

10. In a skip hoist, in combination, drum means, a gear fast to said drum means coaxially therewith, a pair of pinions meshing with said v gear and having their axes in the same plane and parallel with the axis of said gear, intermediate speed shafts for driving said pinions, a motor for each of said shafts, and independent speed reducing means disposed between each of said m0- tors and its corresponding intermediate speed 10 shaft, said motors being located adjacent to each other with their axes in substantially the same plane as the axis of said gear, the axes of said motors being disposed upon the two sides of the axis'of said drum.

GORDON FOX.

OLAF C. CALLOW.

CHARLES G. BIGELOW. 

